Hoisting mechanism



June 19, 1945. BRQWN 2,378,749

HOISTING MECHANISM- Filed Sept. 8, 1941 2 Sheets-Sheet I 9 a K 21 I 1 v .2 6 I 21 In I Z2 f Il I! 5 27 C i 49 I? v; I.

I 34 36 x A ifflrown 3y MW June 19, 1945. BRQWN I 2,378,749

I-LOISTING MECHANISM Filed Sept. 8, 1941 2 Shets-Sheet 2 Patented June 19, 1945 UNITED-STATE PATENT 9 OFFICE HOISTING MECHANISM Arthur J. Brown, Chicago, 111., assignor to Whiting Corporation, Harvey, 11]., a corporation of Illinois Application September 8, 1941, Serial No 409,919

'5 Claims. (c1. 254 1's7 The invention relates to hoisting mechanism.

One object of the invention is toprovide hbisting mechanism of thedrum and cable type which is more particularly adapted for hoisting loads,

such as bombs, and is usable on airplanes. 9

Another object of the invention' is to provide hoisting mechanism of this type which includes a device for operating the cable to move the load which will become inoperative when the load exceeds a predetermined maximum so that in the event of excessive loading or resistance Other objects of the invention will appear from the detailed description.

The invention consists in the several novelfeatures hereinafter set forth and'more particularly defined by claims at the conclusion hereof.

In the drawings: Fig. 1 is a side elevation of hoisting mechanism embodying the invention.

Fig. 2 is a horizontal section taken on line 2-2 of Fig. 1. Fig. 3 is an end elevation. Fig. 4 is a section taken on the line 4-4 of Fig. 1. Fig. 5 is a detail of one of the friction rings for driving the lifting drum. Figffiis a detail illustrating the manner ofsecuring one end of the hoisting cable to the drum. Fig. 7 is a section through the friction-rings and the studson which they are carried. Fig. 8 is a detail section of one of the clampin devices for securing the cable to the drum. Fig. 9 is a section taken on line 9-9 of Fig. 1. 9 9 9 The invention is exemplified in hoisting mechanism which comprisesa "gear-case a which is horizontally divided and includes a base section a, a removable cover section a and an integral under frame a for supporting the case a on the casing of an engine. The frame a has inturned flanges at its lower end which are adapted to rest on the engine-casing, and comprises 9 an arched members a which are joined to and extend between said flanges, and vertical cross- -webs a which are spaced apart to receive between them an ear Ill on a bracket I!) which is. adapted to be'secured to the engine casing. A

pin l i is adapted to extend through holes in the webs a and an upstanding earonthe bracket H! to hold the frame down on the engine-casing.

-A .spring-clip l2 is mounted on the frameand adapted to hold a handle l3 on the pin l l in its locking position. The base a of the gear-case is provided with integral extensions or lugs 49 in which handles 50 are secured, so that the case and mechanism supported thereby can be conveniently transported. This exemplifies a gearcase for hoisting mechanism which can be readily attached to and detached from the casing of anengine.

The hoisting mechanism comprises a drum l5 which isfixed on a shaft [6. The ends of the shaft iii are journaled in a bearing l8 which is supportedfrom one side of the frame a and in a bearing 19 supported in one side of the gear case a. A hoisting cable 20 is fixed to the outer side of the druml5 by an annular series of four clamps. In hoisting mechanism used on airplanes it isdesirable to reduce weightand, for that purpose, the cable is secured by parts formed of aluminum. Plugs 22 of aluminum are screwthreaded into one side of the drum and clamps 2i ofaluminum secure the cable by means of screws Zla. An eye 23 is usually connected to the free end of the cable 20 for connectionto a grapple by which the load may be connected to the cable for transportation or to other means.

An electric motor 0, mounted on one side of the case a with its axis parallel to the axis of the drum, furnishes .power for driving the drum through speed-reducing gearing in case a. This gearing comprises a ring-gear 24 which is fixed to an integral extension l5 of the drum l5; a

pinion'25 which meshes with gear 24 and is integral with a shaft 25 which is journaled in bearings 2'! in the sides of the case a, respectively; a

gear 23 keyed to shaft 26; a pinion 29 which meshes with gear 28 and is fixed on :a shaft 30 which is journaled in bearings 3|. mounted in the sides of the case a; a gear 3| which is rotatable around shaft 30 and is adapted to drive shaft 30 through a friction-device hereinafter described; and a pinion 32 on, and driven by, the shaftof electric motor 0. The inner end of extension w is closed by a plate l5 to prevent the escape of lubricant through thedrum.

In hoisting mechanism used on or in connection with airplanes it is important to automatically limit the power applied to the lifting cable to a predeterminedmaximum load, to prevent gear 3| and the shaft3ll of the pinion 29. This clutch comprises a member or sleeve 33 which is keyed to shaft 30 and provided with an indisks 38, and is adapted to force the outer por-.

tion of the disks against ring 31 which clamps the wheel 3| against the ring 34. Collar 41. isscrewthreaded to sleeve 33 so it canbe adjusted axially to vary the pressure of the outerportionof' disks against ring 3'l-and to vary the clamping pressure between rings 34, 31 and the friction faces on wheel 3|. A screw 4| in collar 4| is adapted to lock said collar in it adjusted position. Ring 34 is connected to flange 35 by studs 42 which are screw-threaded to said ring and are provided with integral pins 43' which pass through holes in said: flange; Ring 3:! issimil'arlyconnected by studs. 42 to: disks 38.. Wheel 3| is axially movable on sleeve; 33; so that the pressure of ring 31 against friction-face 3r|i will force the friction face 36 against ring 34, and frictionally clamp said wheel. betweensaid. rings.

The outer sides of rings 34, 31 are convex in cross-section sov the inner: faces of the. rings will be: free for self alignment with; the: friction faces 36; 36 The gear case. a contains oil for lubricating the gearing therein". The clutch mechanism operates in the case. a where it contacts with a considerable portion of the-oil splashed around the case by the gearing. Each ring 34, 31'! is provided on its inner face: with circular ribs 45 which are spaced apart by annular: grooves 43. Ribs: 45 haveflatnarrow inner'facesv which fit? against the friction faces 36; 36. of wheel 3|, and constitute friction. surfaces of small or limited' area. The resilient disks 38 areadjusted to produce suflicient pressure per square inch between. the: rib-faces: and the opposite friction facesv on wheel. 31 to break down any tendency of the oil: splashed onto the wheel 3| and the rings. to; form. a film between the engaging surfaces of. saidrings and wheel-.. Asa result of: concentrating sufiicient pressure. on the small areas of the rib-faces, and. breaking. down. an oil-film between the. engaging areas of the driving and driven members of the clutch, a substantially constant coefii-cient of friction is maintained for driving the hoisting mechanism. This prevents slipping; of the clutch under normal loads. and the resultant. wear on the: engaging areas; This exemplifies. a friction: clutch in a gearcase containing oilfor lubricationwhichis adapted to become ineffective. under a loadin excess 'of a predetermined maximum, and to drive normal loads with a substantially constant coefficient of friction.

The shaft 301 is extended through one side of the gear-case a-, as at. 29?; so that in the event that electric current i not available for the motor: or' it is desired to manuallyhoi-st: theload, a crank: 23 can. be" connected tosaid shaft. Between: the inner portion |5e on which: the ring gear 2-4 is secured and. the cable winding portion of the hollow drumwhich is. disposed out- .side of the gear-case, the drumis provided: with an annularly grooved. portion. which. extends through one side of thegear-case. An. oil-ring 5| is provided, between said annularly grooved portion of the drum and the case;- for. preventing the escape of oil from the casing around the drum. A screw-cap 53 is provided to enclose the end 29 of shaft 29 when the crank is not in use. An oil-deflector is secured on the inside of a removable plate 56, which is bolted to cover a In the normal operation of the hoisting mechanism, the pressure exerted in. an. axial directionby the disks 38, causes rings 34, 31 to be frictionally engaged by the gear-wheel 3| with sufficient force to drive shaft 30, pinion 29, gear 2'8, shaft 26, pinion 25, gear 24 and drum Hi to shiftqcable 23 and a load of the predetermined maximum on the cable. When the load on the cable doesnot substantially exceed the predetermined maxim-um. such, for example, as a bomb, the friction drive will be eifective to drive the drum. and operate cable 23 to move the load. If

the load. is blocked or attempt is made to hoist a load on the cable 20 which substantially eX- ceeds: the.- predetermined maximum, gear 3|. will continue: to be driven. and rings 34 and 31; will slip on. the gear. so that no excessive stresses will bee-applied.toithecable. Axial adjustment of collar 4| on sleeve;- 33'will. vary the pressure of ringv 3.! against. gear-wheel 3|, so that the friction drive. will remainoperative under predetermined loading. This, feature.- is of. importance because an excessive or a. blocked: load, if the opena-tion of; the: drum: is continued; will exert stresses. on the cable whichv are likely to damage the airplane. The friction drive included in the a. hoisting mechanism which is provided with;

means whereby it may be carried about. and quickly mounted. on, and demounted from, the engine.

The invention is not to be understood as restricted to the. details set forth. since these may be modified. within the-scope of the appended claims; without departing; from the spirit and scope of the. invention- Having thus described the invention, what. I claim. as new and. desire tosecure by Letters Patentisr 1. In hoisting mechanism, the combination of agear-case, a frame on the gear case, a winding drum for a cable supported by said gearcase and said frame, an electric motor mounted on the gear-case, and speed reducing gearing in the gear-case and. between the motor andthe drumv comprising a gear connected to be positively driven. by the motor, a wheel connected to positively drive the drum, a resilient disk rotatable with. said Wheel and rings carried by and rotatable. with the disk and wheel, respectively, and provided with ribs. having narrow faces spaced apart for engaging the opposite sides of said gear for frictionally'driving. said Wheel from said gear and automatically slipping the drum when. the load substantially exceeds a predetermined maximum.

2. In hoisting: mechanism; the combination of agear-casea frame on. the gear case, a. winding gear-case between the motor and the drum comprising a gear connected to be positively driven by the motor and a wheel connected to positively drive the drum, a resilient disk rotatable with said wheel, rings carried by and rotatable with the disk and wheel and having ribs provided with substantially annular narrow spaced apart faces for engaging the opposite sides of said gear for frictionally driving said wheel from said gear and automatically slipping the drum when the load substantially exceeds a predetermined maximum, and connectionsbetween said rings and the disk and the wheel which permit self alignment of said faces of the rings with the gearwheel.

3. In hoisting mechanism, the combination of a gear-case, a frame on the gear-case, a winding drum for a cable supported by said gear-case and said frame, an electric motor mounted on the gear-case, and speed reducing gearing in the gear-case between the motor and the drum comprising a gear connected to be positively driven by the motor, a wheel connected to positively drive the drum, 'a resilient disk rotatable with said wheel, rings engaging the opposite sides of said gear for frictionally driving said wheel from said gear and automatically slippin g the drum when the load substantially exceeds a predetermined maximum, and studs carried in said rings and loosely connecting the rings to the disk and wheel, respectively, for permitting self alignment of the rings with the disk and wheel, respec tively. 4. In portable hoisting mechanism, the com versely inclined base flanges at its ends adapted to rest on an engine-casing, a longitudinally arched member between the flanges and crossmembers connected to said member and centrally disposed adjacent the longitudinal center ofthe frameadapted to lap a lug on a bracket secured t on the engine, and a pin for locking the overlap ping members and the lug together and detachably mounting the frame and gear-case on the engine-casing. i

5. In portable hoisting mechanism; the combination of a gear-case, an electric motor mount ed on one side and on the outside of the gearcase, a drum for a cable, speed reducing gearing in the casing for driving the drum from the m0- tor, a frame below and integral with a portion of the gear-case, the frame comprising transe versely inclined base flanges at its ends adapted to rest on an engine-casing, a longitudinally arched member between the flanges and'webs connected to said member and centrally disposed adjacent the longitudinal center of the frame and adapted to lap a lug on a bracket secured on the engine, and a pin for locking the webs and the lug together for detachably mounting the frame and gear-case on jthe engine-casing.

ARTHUR J. BROWN.

.bination of a gear-case, an electric motor mounted on one side and on the outside of the gearcase, a drum for a cable, speed reducing gearing in the casing for driving the drum from the motor, a frame below and integral with a portion of thegear-c-ase, the frame comprising trans 

